Age-related Macular Degeneration (AMD)

What is Age-related Macular Degeneration (AMD)?

Age-related Macular degeneration (AMD) is a condition that is often linked to old age, and causes a loss of central vision typically in both eyes, and is most common. AMD has been shown to be the leading cause of vision loss in the UK with more than 600,000 people affected. It also tends to be more common in women than men, and there is a high prevalence amongst white and Chinese people for reasons unknown. A number of factors are thought to increase the risk of developing macular degeneration including age, obesity, excessive alcohol consumption and smoking.

There are two major types AMD; dry AMD where the loss of vision is gradual, compared to wet AMD where if left untreated can cause a deterioration if vision within days. An estimated 1 in 10 people with dry AMD progress to having wet AMD.

What is Age-related Macular Degeneration (AMD) caused by?

What exactly causes macular degeneration remains unknown, but we do know that the condition develops as the eye ages. Dry AMD is caused by damage to the macula cells due to a build-up of waste products in the retina, causing deposits called drusden. Wet AMD on the other hand is caused by the development of abnormal blood vessels that form under the macula which causes cellular damage.

What are the symptoms of Age-related Macular Degeneration?

The most common symptom is gradual worsening vision. This can include where reading becomes harder, less vibrant colours, and it becomes increasingly difficult to recognise people’s faces. Other symptoms include; blind spots in vision, loss of fine detail vision, unclear images. Distortion of images in the centre and is another symptom which is mostly associated with wet AMD.

How is AMD treated?

Currently there isn’t a cure for either type of AMD.

There is a little evidence to suggest that a diet high in vitamins A, C and E found in leafy dark green vegetables may be helpful in slowing the progression of dry AMD. Practical tips include the use of magnifying lenses, large print books and bright reading lights.

Treatment for Wet AMD is either one of two options. The first being anti-VEGF (vascular endothelial growth factor) medication which would stop the growth of blood vessels in the eye. The injection doesn’t restore vision completely, but will restore some vision. There are two anti-VEGF treatments available on the NHS; ranibizumab and aflibercept, where your ophthalmologist will be able to tell you which one is suitable for you. Other treatment include photodynamic surgery where vertporfin, a light sensitive medicine is injected into your arm. It then attaches itself to the abnormal blood vessels in your macular, where is activated by a laser light to destroy the abnormal vessels.

Laser photocoagulation is another form of surgery used for treating wet AMD. However, it is only suitable if the abnormal blood vessels are not close to the favela, as it can cause permanent vision loss, so the pros and cons of this treatment need to be discussed with your doctor.

Newer types of surgery include macular translocation where the macular is moved over to a healthier section of the eyeball which has healthy blood vessels, and lens implantation, where an artificial lens replaces the damaged lens.